Put the verbs in brackets into the past perfect or the past perfect continuous.

In 1990, two friends, Robert and Barry, managed to survive the harsh conditions of the Sahara desert alone for two days. The two friends 1) (enrol) in the Marathon of the Sands which was a seven day foot race through the Sahara desert. Before the competition began, they 2) (pack) all the food, clothing and supplies they needed for their desert adventure in large rucksacks, which they carried on their backs. On the first day of the event the two friends 3) (walk) in the desert for a few hours when all of a sudden a sand storm appeared out of nowhere. They had nowhere to take cover. Robert opened his rucksack only to realise that he 4) (forget) to pack their compass. Terrified, the men sat in the middle of the sand storm and waited for help to arrive. They 5) (wait) for two days before the organisers of the event realised that the two men were missing. The organisers sent a rescue team which eventually found them. The two men felt extremely lucky to be alive!